hicks



(No Model.)

T. H. HICKS.

ALTERNA'TINGIOURRENT DYNAMOi No. 465,855. Patented Dec. 29, 1 89-1.

awwewtoz IlNiTED STATES PATENT 'FFIQE.

THOMAS II. HICKS, OF DETROIT, MICHIGAN, ASSIGNOR OF ONE-HALF TO H. L. OBETZ, OF SAME PLACE.

ALTE RNATING-CURRENT DYNAMO.

SPECIFICATION forming part of Letters Patent No. 465,855, dated. December 29, 1891. Application filed January 3, 1891. Serial No. 376,613. (No modehl To all whom, it may concern.

Be it known that I, THOMAS H. HICKS, a subject of the Queen of Great Britain, residing at Detroit, countyof \Vayne, State of Michigan, have invented a certain new and useful Improvement in the Construction and Operation of Alternating-Onrrent Dynamos; and I declare the following to be a full, clear, and exact description of the same, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, which form a part of this specification.

This invention relates to new and useful improvements in alternatingcurrent dynainos, as explained and set forth in the following specification and claim, and illustrated in the drawings hereto annexed, in which- Figure 1 is a diagram representing four coils removed from the armature and spread out, so as to show the manner of winding the armature-coils, the manner of forming them in series, and the relative direction of induction. Fig. 2 is a diagram of one armaturecoil. Fig. 3 is an end view of the armature- ,windings, their connections with each other and with the collecting-rings, and the position of the field-poles, shown partly cutaway. Fig. 4 is a side elevation, partly in section, showing the armature, two of the field-coils, the commutating device, and an inductorium for supplying current for the field-coils and other uses after having been convert ed into a continuous current, in combination with the 'connnutating device referred to. Fig. 5 is a diagram view of a coil distinguished from Fig. 2 for purposes of illustration in having no opening analogous to the space B Fig. 2, between the convolutions on each side of the center of the coil.

In constructing the dynamo the field-poles A are made of such'a width and arranged around the armature B in such a manner that each of the spaces between the field-poles is rents in opposite directions, and are equal to one-third the total width of the coil or the width of one field-pole. The opening is shown in Fig. 2 at B My objectin winding each coil, so as to form the opening B is to have each coil either cutting the magnetic lines of force of two poles of opposite magnetic sign, or elsedischarging its induced current when hetween'the holes, and not have one side of each coil always under a magnetic pole While the other side of the coil is between the poles, as must occur when the space is not left, or, in other words, as shown in a diagram'view in Fig. 5. In the latter case all of the conductors forming one coil can never be n11- der the inductive action of two field-poles at the same time, which should be the case if strongest induction is to take place. Two of such coils, as shown in Fig. 2, are joined together, constituting a pair of coils in series, and any number of such pairs may be further arranged together in series or multiple or multiple series, a linear series of two pairs being shown in Fig. 1.

In arranging the coils (shown in Fig. 2) around the armature the space E of one coil is filled with one-half of its fellow coil, which is used to form a pair of coils in series, the two coils crossing each-other on the end of the armature, as shown in Fig. 3 at O O C O and in Fig. 1 also, indicated by similar letters. The terminals of the total series of pairs of coils end in collector-rings, marked D D, (shown in Figs. 1, 3, and 4,) as is usual in all alternating-current dynamos. The portion of the armature claimed to be new, which is the arrangement of two coils in pairs, having one-half of each coil laid between the spaces B of each other, having been fully described, I will now describe the devices and explain the modus operand-z) of said devices used to strengthen the alternating current generated in the armature, so that the combination will constitute an auto or self-exciting alternating electric-current machine.

- In Fig. 4, as above observed, B is the armature, A A are two of the series of field-poles shown in Fig. 3, D D are the collector-rings of'the armature, and E E is an external circuit conveying the alternating currents from the armature to an inductorium F, where a portion of the alternating current is either increased or reduced in electric pressure, as may be desired, through the converting-coil marked II. The current is then conveyed through the circuit J J to a commutating device K K, which is rotated together with the armature B. The commutator-sections K in circuit with conductor J are alternately arranged with the sections K which are in electrical circuit with conductor J and the two sets of bars K and K equal in total number the number of field-poles A, as is common in all alternating machines. Thus it will be readily seen that when the armature rotates the alternations in the direction of current impulses through the converter will be synchronous with the commutator chan ges. The commutator being rotatable with the same shaft M, carrying the armature, currents can be taken off from the brushes L and L to supply not only the field-coils A, but any other translating devices placed in proper circuit, as an arc lamp (indicated at O) and motor, (indicated at Q.) Translating devices may also be arranged in the converted alternating circuit J J and in an alternating circuit R, which is in multiple are with the primary coil S of the converter or inductorium F. The switch N is for the purpose of either cutting in or out coils of the secondary circuit for the purpose of changing the electro-motive force in the continuous-current circuits, which in return causes a corresponding change in voltage in every circuit in connection with the dynamo. Branch wires n n are taken off from appropriate convolutions of the coil II and terminate in buttons,(marked 0c 00,) the switch-bar N being free to move over the button, and thus vary the length of the induction-coil supplying induced currents to the circuit J J.

The direction of currents is indicated by arrow-heads located upon the various circuits. Some circuits have both dotted and full arrow-heads. Such circuits are traversed by alternating currents, the full arrowheads indicating the direction of the current impulse when the brushes L and L are in contact with the commutator-sections, as indicated. Conductors where only full arrowheads are shown indicate continuous-current circuit.

The many advantages to be gained by sen ding out a high-potential alternating current and then returning a portion of it having a reduced pressure for commutation will be readily appreciated from the following considerations:

First. It is impossible to straighten an al* ternating current of high potential where the field of force of the alternating machine is maintained from electricity supplied from an independent source without great danger of short-circuiting the alternating current di rectly through the armature, which would result in aburned-out armature; but if the converted current should become short-cireuited through either the commutator or secondary coil the field-poles would therefore not be supplied with current. Consequently the voltage would instantaneously d rop to almost nothing, which would therefore save the armature from the aforesaid danger.

Second. Supplying the fields with current from a separate dynamo requires resistance to be placed in the field-circuit for the purpose of varying the strength of the magnetic fields of force. This costs power to overcome; but when supplied through a converter the eleetro-motive force can be varied at pleasure by either cutting in or out convolutions of the secondary coil. In this way all variations in armature speed can be compensated for and without additional cost.

Third. Alternating-current generators can be used having but a fraction of the armature resistance necessary in continuous-current generators for isolated plants. This means good regulation and economy.

The incandescent lamps can be supplied directly from the alternating -current collector-ring brushes having a voltage suitable forsuch isolated lighting plants, and at the same time any desired low-potential continuous current can also be taken off for electro-plating or other purposes by winding or changing the field-resistance to suit the continuous-current voltage from which the fieldcoils are supplied.

Having thus explained the meehanicalconstruction and arrangement of the various parts necessary for carrying my invention into effect and pointed out the advantages to be gained thereby, I therefore claim as new, and desire to secure by Letters Patent, the matters hereinafter enumerated.

hat I claim as my invention is-- In an alternating-current dynamo, the combination, with field-poles of opposite magnetic signs alternately arranged at equal distances from each other and each made of a width equal to the distance each is spaced from the adjacent pole, of an armature wound with coils arranged in pairs, each coil having convolutions forming a central opening, the width of the opening and of the parallel conductors on each side of the opening each of a width equaling the width of one of the fieldpoles, the two coils of each pair crossing each other at the ends of the armature and filling the said spaces of one another, each pairof coils when arranged upon the armature occupying an arc of its circumference equal to the width of two field-poles and two field spaces and extending the length of said armature, and two or more of said pairs arranged in linear series with each other, substantially as set forth.

In testimony whereof I sign this specification in the presence of two witnesses.

THOMAS H. HICKS.

Witnesses:

N. S. WRIGHT, J OHN F. MILLER. 

